let
Source = Table.NestedJoin(Data,{"Category"},LookupTable,{"Category"},"LookupTable",JoinKind.LeftOuter),
#"Added Custom" = Table.AddColumn(Source, "ReturnValue", each Table.Column([LookupTable],[RequiredField]){0}, type text),
#"Removed Columns" = Table.RemoveColumns(#"Added Custom",{"LookupTable"})
in
#"Removed Columns"